The following relates generally to wireless communication, and more specifically to User Equipment (UE) beam search and selection in millimeter wave systems.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems, (e.g., a Long Term Evolution (LTE) system, or a New Radio (NR) system). A wireless multiple-access communications system may include a number of base stations (e.g., a gNB, TRP, eNB) or other network access network nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).
In some wireless systems, base stations and UEs may communicate using directional transmissions (e.g., beams), where beamforming techniques may be applied using one or more antenna arrays to generate beams in different directions. For example, a base station may transmit downlink communications (e.g., synchronization signals, signals, data signals, etc.) to a UE using a transmit beam in a particular direction, and the UE may in turn receive the downlink communications on a receive beam in an opposite direction. In very high frequency systems a base station may transmit using narrow beams to overcome path loss. A UE may be able to receive on many suitable down-like beams from one or more gNBs. Searching and tracking a large amount of beams increases complexity and consumes modem and RF power. It may thus be desirable to improve techniques for downlink beam selection in beamformed communication systems.